Subsurface soil injection method

ABSTRACT

A method for the subsurface application of fertilizers, biologicals, fumigants, non-fumigant pesticides or other chemicals to soil with reduced application rates. Discrete amounts of the materials are injected into the soil at numerous sites along a path during a pass through the soil. At the injection sites, the materials form diffusion patterns which may touch or overlapping with diffusion patterns of adjacent soil injections. The application of materials to soil in this manner maintains optimum efficacy with the use of the least amount of materials necessary per acre of soil.

This is a divisional of Application Ser. No. 09/794,062 filed Feb. 28,2001 now U.S. Pat. No. 6,990,912; the disclosure of which isincorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to apparatus and distinct methodology thatwill improve the delivery of iodomethane or an alternative substanceincluding but not limited to fertilizer, fumigants, non-fumigantpesticides, biologicals and other chemicals (hereinafter “products”) toprepare the soil for planting.

2. Description of the Related Prior Art

Methyl iodide is known for use as a soil fumigant. As described in U.S.Pat. Nos. 5,753,183, and 5,518,692, methyl iodide (hereinafter“iodomethane”) has been used for the effective control of soil borneplant pathogens such as fungi, bacteria, viruses, nematodes, insects andarachnids (including eggs, larva, pupae and adults).

Also, there are devices and systems for applying substances or chemicalsto soil. One such system is described in U.S. Pat. No. 6,029,590 whichrelates to an apparatus and method for the subsurface application ofchemicals such as fertilizers, pesticides and fumigants in soil.

Known devices for application of chemicals to soil apply a constantstream of the material to the soil during a pass through the soil,either by spraying the material or applying it in some other constantmanner. Thus, the fumigation equipment in use today distributes materialin a continuous flow in a targeted area. Concomitantly, there is a largeamount of the material applied to the target area. There is a need for amore efficient and accurate distribution of chemicals into the targetsoil area.

SUMMARY OF THE INVENTION

In accordance with the present invention, an apparatus is provided forintroducing a discrete, predetermined amount of a material into soil atpredetermined intervals in the soil. The apparatus includes a containerfor holding the material to be introduced into the soil, and tubingconnected to the container at one end and having a distal end forintroducing the material into the soil. One or more shanks are providedfor placing the distal end of the tubing at a predetermined depth in thesoil during introduction of the material into the soil. A switch (suchas a solenoid switch) is provided for controlling flow of the materialthrough the tubing. The switch is operable between an open state forintroducing the discrete, predetermined amount of the material into thesoil at a predetermined point in the soil, and a closed state when theshank is positioned between the predetermined points in the soil.

A method for applying a material to soil is also provided in accordancewith the present invention. The method includes the step of introducinga discrete, predetermined amount of the material into the soil atpredetermined intervals or distances along a linear path in the soil.The material diffuses into the soil from each point to provide diffusionpatterns that may overlap dependent upon its targeted pest and crop (forexample, tree and vine may not have overlapping patterns) in the soil.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of a tractor mounted system in accordance with thepresent invention;

FIG. 2 is a perspective view showing a shank portion of an apparatus forinjecting fumigant in accordance with the present invention and severalinjection points;

FIG. 3 shows an apparatus suitable for injecting fumigant into soil inaccordance with the present invention;

FIG. 4 shows two shanks injecting fumigant into the soil in accordancewith the present invention; and

FIG. 5 is a perspective view showing two shanks injecting fumigant intoa row of soil in accordance with the present invention as they travelthrough the soil in the direction of the arrow.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In accordance with the present invention, a new method of application ofproducts is provided that may achieve better delivery with moreefficient and accurate distribution into the target soil area. Soiltreatment by the method of the present invention should lower rates overwhat is currently used given the improved mechanism of delivery of thepresent invention. Compounds injected into the soil in accordance withthe present invention include iodomethane, but the present invention isnot limited to the application of iodomethane or even fumigants.Application of other compounds, such as fertilizers, biologicals, andnon-fumigant pesticides, either alone or in combination with iodomethaneare also within the scope of the present invention. For example, theapparatus and method of the present invention may be used to introducethe following chemical and biological materials into the soil: thefumigant chloropicrin (trichloronitromethane) available from NiklorChemicals Mojave of Long Beach, Calif.; the fumigant Telone-35(1,3-dichloropropene and 35% chloropicrin) available from DowAgroSciences of Indianapolis, Ind.); the fumigant propargyl bromide(3-bromopropyne) available from Albermarle Corporation of Baton Rouge,La.; the liquid biological nematicide Ditera (a natural product from thehyphomycete fungus Myrothecium spp. composed primarily of proteins,sugars and lipids) available from Valent BioSciences of Libertyville,Ill.; the liquid Plant Pro 45 (3% iodine based ingredient) availablefrom Ajay North America of Powder Springs, Ga.; the liquid fertilizerCAN-17 (calcium aluminum nitrate 17% solution) available from Prodica ofBrea, Calif.; the liquid fertilizer UN-20 (nitrogen urea 20% solution)available from, among others, Soil Serve of Salinas, Calif.; and liquidBacillus subtilus suspended in aqueous solution available from AgraQuest of Sacramento, Calif. Other chemical and biological materials suchas Pseudomonas sp. suitable for injection into soil in accordance withthe present invention will be apparent to one skilled in the art. Thematerial introduced into the soil in accordance with the presentinvention may be either a liquid or gas.

Materials introduced into the soil in accordance with the apparatus andmethod of the present invention which include a volatilizing ingredient,such as fumigants, will form a diffusion pattern that advantageouslyspreads out in all directions from the injection site. Materials such asfertilizers which do not contain a volatilizing ingredient, aretypically placed at or near the root zone of the plant. In accordancewith the apparatus and method of the present invention, these types ofmaterials may be precisely placed at this location. Thus, while thesetypes of materials lack a volatilizing ingredient, they can be preciselyplaced within the root zone and form a desired diffusion pattern, albeitnot in all directions through the soil. Thus, the user may introducematerial into soil in accordance with the present invention to formdiffusion patterns of the material in the soil at adjacent injectionpoints which touch, overlap or are intermittent, i.e., are not touchingat all, as desired.

The invention is described herein in connection with the soil fumigantiodomethane. As discussed above, however, it being understood that thepresent invention is not limited to the introduction of solely thismaterial into soil.

Efficacy testing using known application equipment with iodomethane hasshown irregularities in product distribution within the soil. In thisregard, conventional flow meters, tubing and orifice sizing and a radarequipped digital system have shown to be unreliable in accurate andconsistent delivery of a target rate (gal/treated acre, lb/treated acre,or liters/treated hectare) to the soil applied by multiple types ofshanks (either flat/broadcast or bed shank). Fluctuations in the knownsystems of delivery when applying iodomethane (in contrast to theapplication of methyl bromide, another fumigant being phased out becauseof environmental regulations) are thought to be in part the result ofdifferences in the physical properties between iodomethane and methylbromide. Conventional equipment is specific to a single chemical (forexample, methyl bromide) and does not provide adequate crossover for usewith other materials. For example, the density of iodomethane is 2.3g/L, while the density of methyl bromide is 1.7 g/L. In any event,fluctuations in delivery of the fumigant results in either too much ortoo little compound being applied and/or irregular patterns of materialbeing distributed in the treatment area.

In accordance with the present invention, problems in fluctuation ofapplication of iodomethane using conventional systems are avoided. Asingle injection point in accordance with the present invention willhave a maximum distribution or diffusion pattern (“affected treatmentarea”) in the soil of the applied chemical or chemicals that if desired,touches or overlaps with diffusion patterns from adjacent injections

In accordance with the present invention, the amount of materialintroduced into the soil for treatment thereof may be reduced. In thisregard, the diffusion pattern can be determined for a given fumigant ina given soil type with single injection points at equal intervals inaccordance with the present invention overlapping in the gas phase, forexample, and moving equally through the soil profile or column.Conventional equipment does not allow for injection of materials atprescribed intervals in a linear pattern, as in the present invention.Accuracy in delivery of soil fumigants in accordance with the presentinvention will provide for significantly reduced application rates,reduced worker exposure and greater safety in application and handling,less cost per acre to the grower and significantly reduced emissions offumigant into the atmosphere.

In accordance with the present invention, fumigation rates, for example,may be reduced by about 40%, and in some cases the reduction may be upto about 50%, depending on soil conditions and other factors, comparedto conventional systems for applying fumigants. For example, ifinjections are made at one foot intervals in accordance with the presentinvention, as opposed to a conventional continuous flow, then areduction in the applied rate of 50% can be expected from a traditionalbed shank treatment.

The amount of treatment material applied to the soil in accordance withthe present invention will vary depending upon the material beingapplied to the soil, soil conditions, etc. For the fumigant iodomethane,for example, the fumigant may be applied in an amount of preferablyabout 3 gal/treatment acre to about 12 gal/treatment acre, morepreferably 3 gal/treatment acre to about 9 gal/treatment acre, and mostpreferably about 3 gal/treatment acre to about 6 gal/treatment acre.

Iodomethane, a preferred fumigant for use in the apparatus and method ofthe present invention, is a colorless liquid at 20° C., and will flowthrough injection equipment and/or tubing at ambient room temperature.Its solubility in water is 14.2 g/L, such that it can be mixed withwater without the use of emulsifiers. Further, iodomethane in thepresence of light turns orange-brown and rapidly photodegrades. Itslifetime in the atmosphere is 1.5-4 days, which inhibits it fromreaching the ozone layer and therefore iodomethane is classified as anon-ozone depleting compound (the ozone depleting potential of methyliodide is 0.0015 as reported by Ko, “Estimates of Atmospheric Lifetime,Global Warming Potential and Ozone Depletion Potential of Iodomethane(CH₃I)”, Executive Summary III, Atmospheric and Environmental Research,Inc. (Report Date Oct. 31, 2000). The corrosiveness of iodomethane tocarbon steel has been documented and in some cases iodomethane has beencorrosive to poly vinyl chloride (PVC) pipe. Accordingly, there shouldbe the appropriate selection of materials for handling iodomethane, asone skilled in the art would recognize and address in a suitable manner(as discussed below suitable materials for handling iodomethane arecommercially available). The volatility of iodomethane is similar tothat of methyl bromide. Iodomethane has a Henry's Law Constant of 0.22compared to 0.24 for methyl bromide, which means that iodomethane, likemethyl bromide, will change from a liquid to a gas once it is injectedinto the soil. The molecular weight of iodomethane is 141.9, and it hasa density of 2.28 g/ml. Iodomethane is non-flammable and non-explosive,and it currently finds uses in the fields of medicine, organicsynthesis, microscopy, and testing for pyridine.

While not wishing to be bound by theory, it is believed thatiodomethane's mode of action as a fumigant is through the bimolecularnucleophilic displacement (SN₂) reaction with functional groups such asNH₂ and SH, in various amino acids and peptides in target organisms.

In accordance with the present invention, iodomethane can be introducedinto the soil as a stand-alone product or in combination with other soilfumigants, e.g. chloropicrin or other products such as biologicals,etc., and it is injected into the soil for control of soil born pestsand disease.

Referring now to FIGS. 1-4, the soil injection apparatus in accordancewith the present invention is preferably mounted to a vehicle such as atractor 10 for delivery of the material into the soil. Other vehicles,for example, a pick-up truck, may of course be used to transport theapparatus.

As shown in FIG. 2, tractor 10 may be used to make a single pass throughsoil 12 with shank or shovel 20 allowing for injections of fumigant atpoints 30 at pre-determined intervals, for example, 6 inches apart alonga linear path. The fumigant iodomethane, for example, may be injectedinto soil in accordance with the present invention at substantiallyequidistant points in the soil preferably at about 3 to about 12 inchesapart, more preferably about 5 to about 12 inches apart and mostpreferably about 8 to about 12 inches apart.

The shape of shank(s) 20 is not limited, and shank(s) 20 may have anysuitable shape provided it allows for injection of material into thesoil in accordance with the present invention.

As discussed above, in the case of fumigants containing a volatileingredient the material enters the soil as a liquid but quickly turnsinto a gas where it travels in all directions through the soil porespaces providing control of target organisms within a distinct layer ofthe soil profile with minimum disturbance to soil structure. This isshown in FIGS. 1 and 5 as diffusion areas 40.

As one skilled in the art will appreciate, the distance betweeninjection intervals is dependent upon the diffusion pattern of theinjected material in the soil. These patterns are influenced by soiltype, condition and target organism to be controlled. Thus, as describedabove, the injection points may be anywhere up to about 12 inches apartfor iodomethane, but distances between injections of beyond 12 incheseven for iodomethane are within the scope of the invention dependingupon soil conditions, etc. Further, as will be appreciated from thefollowing, material is injected into the soil only when tractor 10 is inmotion and the injection tubes are in the soil, thus maintaining aclosed fumigation system to the treatment area.

The depth of the injection sites in accordance with the presentinvention will vary depending upon soil type and whether the crop to beplanted after fumigation is shallow-or deep-rooted. Examples ofshallow-rooted crops are strawberries and tomatoes, while deep-rootedcrops are trees and vines. For shallow-rooted crops, the depth ofinjection in accordance with the present invention is preferably about 1inch to about 12 inches, more preferably about 1 inch to about 8 inches,and most preferably about 1 inch to about 6 inches, below the surface ofthe soil. For deep rooted crops the depth of injection in accordancewith the present invention is preferably about 18 inches to about 24inches, more preferably about 20 inches to about 24 inches, and mostpreferably about 22 to about 24 inches, below the surface of the soil.

Referring to FIGS. 1 and 3, iodomethane may be stored in a stainlesssteel or other suitable contained 50 mounted on tool bar 14 or othersimilar structure attached to, for example, tractor 10. Alternatively,as mentioned above, container 50 may be transported in any othersuitable manner, such as by a pick-up truck. Material stored in tank 50flows through tubing 60 into a reservoir 70. One-way valve or switch 80at the outlet of container 50 allows material to fill reservoir 70 andalso for gas to prime the reservoir, as will be discussed below. Asource of compressed gas, such as nitrogen or a similar gas is providedby container 82. Compressed gas flows from contained 82 through tubing84 to tubing 86 and 88. A solenoid switch 92 is provided to control theflow of compressed gas in line 102 which is connected to tank 50.Similarly, a solenoid switch 94 is provided in tube 88 to control theflow of compressed gassed therethrough to reservoir 70.

Global Position Satellite (GPS) device 150 or a similar device such as aradar device mounted to the apparatus of the present invention tractsmovement (speed and location) of the apparatus and inputs thisinformation into computer 160. Other information is also provided by auser to computer 160 including the rate of application of the material,number of nozzles, weight/density of the materials, depth of injection,distance between pulses and target ground speed, and computer 160provides the appropriate signals to the apparatus, namely solenoid 92 inaccordance with programming software previously inputted into computer160 by one skilled in the art.

Solenoid switch 90 is provided at the outlet to reservoir 70 and opensto allow material to flow through tubing 100 and out through shanks 20,22, 24, etc. At the appropriate time, gas sensors 100, 112, 114, etc.provide an electrical signal for closing solenoid switches 90 and/or 92(the electrical signal being shown by the solid and hatched lines inFIG. 3). Orifice plate 120, is provided for regulation of variousliquids/gas materials to manifold 130. Flowmeter 140 tracks the rate offlow through tubing 100 and out through tube shank lines 142, 144, 146,etc., to shanks 20, 22, 24, etc. At manifold 130, the material isdivided into equal parts for delivery through tube shank lines 140, 142,144, etc.

A single injection or pulse unit for subsurface soil injection inaccordance with the present invention may be operated in the followingmanner where a single pulse unit is the application or amount of afertilizer, biological or chemical, such as iodomethane, from a storagetank into the lines and out through shanks placed at a predetermineddepth and location in the soil.

First, computer 160 has the following input of data:

1. Rate of Application in amount of material;

2. Number of injection nozzles;

3. Weight/density of the material;

4. Location of treatment area according to GPS coordinates;

5. Depth of injection of shanks;

6. Physical state of material (gas or liquid);

7. Distance between “Pulse Units”; and

8. Ground Speed (Inches/sec).

The equipment is then moved into the treated area and position verifiedby GPS.

The equipment initiates movement and the computer receives input toinitiate a single pulse to the injection system.

Input is received at the solenoid switch 92 to release iodomethane frompressurized storage tank 50 and into reservoir 70. Tank 50 is held at aconstant pressure by input line 102 from nitrogen tank 82.

Solenoid switch 92 closes and the exact amount of material for a singlepulse is held in reservoir 70.

Solenoid switch 94 is opened to allow nitrogen or compressed air topressurize the material in reservoir 70. When the desired pressure isreached in reservoir 70, solenoid switch 90 is opened so that thematerial is released from reservoir 70 and pushed through tubing 100 andout to manifold 130.

At manifold 130, the material is divided into equal amounts dependingupon the number of shanks being driven through the soil.

Pressure is still pushing the material from solenoid switch 90 and willdistribute the material to each shank tube line 142, 144, 146, etc., andout through each nozzle.

Near the nozzle at the end of each shank tube line 142, 144, 146, etc.,there is a gas sensor 110, 112, 114, etc., that determines when theentire amount of material has been expelled from the tubing and thensends a signal to solenoid switch 94 to close and stop the flow of gas.

The equipment continues to travel to the next injection point and isready for the next injection.

The entire injection apparatus should be a closed system to insuresafety to the various personnel involved in mixing, loading and applyingthe fumigant in accordance the present invention. As discussed above,the material to be applied to the soil may be expelled from thecontainer by either nitrogen compressed gas or similar non-reactive gas.Alternatively, one skilled in the art will recognize that the sameresult may be achieved by a pump, the pump being a relatively accuratepump. Thus, injections of material into the soil in accordance with thepresent invention may be made with a positive displacement pump, but ofcourse diaphragm, roller, impeller or other pumps may also be used.

In accordance with the present invention, the quantity of materialneeded for a single injection may be drawn from the tank. The exactamount drawn is determined by the target rate to be applied/acre takinginto consideration the ground speed of the tractor. Ground speed may bedetermined by radar device 130 mounted on tractor 10 (see, FIG. 1) or inany conventional manner, and transmitted to computer 160 that willregulate the feed of more or less of material from tank 50 to tube line60.

As iodomethane is pushed through the nozzle opening at the distal end oftube shank lines 142, 144, 146 etc., and injected into the soil inaccordance with the present invention, it does not create a fan or spraypattern. Instead, a reservoir of material is deposited to a single pointin the soil where it will distribute through the soil and, if desired,overlap with the diffusion pattern or areas of adjacent soil injections.Thus, no special shape of the nozzle is required so long as a suitableinjection in accordance with the invention is achieved. However, thenozzle opening may, if desired, be provided with a valve (not shown)such as a shut-off valve operated by, for example, pressure, or anysuitable one-way valve to inject the material into the soil but preventdirt from entering the nozzle.

In accordance with the present invention, the material is released fromnozzles at the end of tube shank lines 142, 144, 146, etc., attached toshanks or shovels 20, 22, 24, etc., at equal intervals as determined bysoil type, rate, depth of injection, diffusion pattern and target pests.A single injection depth may be determined and used for eachapplication, with the shanks 20, 22, 24, etc., all being within the sameplane. It will be appreciated that the distance between each adjacentshank will depend upon, among other things, the width of the treatmentarea. A preferred spacing between shanks in connection with theinjection of the fumigant iodomethane in accordance with the presentinvention is about 12 inches, as shown in FIG. 4. Referring to FIG. 4,for a soil bed having a 34 inch width, two shanks spaced about 12 inchesapart and about 11 inches from the edges of the bed may be suitable.More generally, for the application of, for example, iodomethane inaccordance with the present invention, adjacent shanks may be spacedabout 6 inches to about 24 inches apart, more preferably about 8 inchesto about 24 inches apart, and most preferably about 12 inches to about24 inches apart. Of course, spacings of the shanks greater than 24inches apart, if desirable, are within the scope of the invention. Forexample, while 20 inch spacings is typical for deep rooted crops, thespacing may be as much as 60 inches apart. Further, tubing 60, 100, 142,144, 146, etc., for transfer of the material through the system and intothe soil should be compatible with the material being injected. In thisregard, when injecting iodomethane into soil in accordance with thepresent invention, tubing material which is durable and will not corrodeshould be used, as one skilled in the art would recognize. For example,when injecting iodomethane, the tubing may be stainless steel or aperfluoroelastomer or fluoroelastomer, such as Kalrez® or Viton®,respectively, both of which are available from Du Pont Dow Elastomers,LLC of Wilmington, Del.

In accordance with the present invention, the apparatus may be chargedwith the amount of material needed for a single injection. Thus, primingthe entire system is not necessary and, between injections, material maynot be present in all the lines. This action makes cleaning of theequipment easier since there is little to none of the material to expelfrom the lines once the target area has been treated. Nitrogen orcompressed air can then be used to rid the lines and to help minimizethe potential for exposure typically associated with conventionalequipment.

The invention may be better understood with reference to theaccompanying example, which is intended for purposes of illustrationonly and should not be construed as in any sense limiting the scope ofthe invention as defined in the claims appended hereto.

EXAMPLE

Iodomethane is injected as a fumigant into soil having the followingcharacteristics: pH of 6-8, organic matter-1-3% by wt., % moisture-50-90(sealed holding capacity), in accordance with the present invention inthe following manner in preparation for planting strawberries in thesoil.

A container of the apparatus is charged with iodomethane, and theapparatus is positioned at a location in the treatment area whereby 2shanks are located in the same plane at a depth of 10 inches in a soilbed 38 inches wide, the shanks being spaced 24 inches apart. Based uponinformation previously inputted into the computerized controls of theapparatus, an amount of 3 ml of iodomethane is drawn from the tank forinjection into the soil by all the shanks and placed in a reservoir.Following opening a solenoid switch at the reservoir, this amount ofiodomethane then flows through tubing by means of compressed gas to amanifold which distributes the iodomethane equally among 2 shank tubelines, each of which has a nozzle associated with each of the shanks. Inthis manner, 1.5 ml of iodomethane is injected from each nozzle into thesoil where the iodomethane immediately vaporizes into a gas and createsa diffusion pattern in the soil that is either spherical or ellipticalin shape, having an effective treatment diameter of about 24 inches. Gassensors located near the nozzles of the tube shank lines determine whenall the iodomethane has been expelled from the shank tubing lines andthe solenoid switch opening the reservoir is closed. The apparatus isthen moved 12 inches in a straight path to a second position whereat asecond injection of iodomethane is carried out by the sequence ofiodomethane transfer and valve openings discussed above.

While the present invention has been described with reference topreferred embodiments and illustrative examples, it should be understoodthat one of ordinary skill in the art after reading the foregoingspecification would be able to effect various changes, substitutions ofequivalents and modifications to the methods as described herein.Therefore, it is intended that the scope of the invention not be limitedby reference to the illustrative example, but rather with reference tothe accompanying claims.

1. A method for applying a product to soil, comprising the steps of:providing a storage tank, which stores the product, in fluidcommunication with a reservoir; providing a plurality of injectorsconnected to the reservoir by a fluid conveying member, said pluralityof injectors being disposed proximate to a plurality of shanks; priminga discrete, predetermined amount of the product, which is supplied fromthe storage tank, in the reservoir by a priming member which pressurizesthe discrete, predetermined amount of the product in the reservoir to apredetermined pressure level; releasing the discrete, predeterminedamount of the product, which is pressurized in the reservoir at thepredetermined pressure level, in response to a control signal; andinjecting the discrete, predetermined amount of the product, which isreleased from the reservoir via the fluid communication member, underpressure at the plurality of injectors, wherein each injectorintermittently injects the product at a series of locations in a passthrough the soil by priming the discreet, predetermined amount of theproduct to the predetermined pressure level in the reservoir after eachinjection point, the product diffusing into the soil from each of theinjection points to provide diffusion patterns of the product in thesoil, wherein the injecting comprises releasing the discrete,predetermined amount of the product as a single charge of the reservoir,which is pressurized by the priming member, at a point in the soil, theproduct volatilizing from that point to form a diffusion pattern of theproduct in the soil that is touching, overlapping or intermittent withdiffusion patterns from adjacent points of releasing the product assingle charges of the reservoir at the injection points.
 2. The methodaccording to claim 1, wherein the product is a fumigant.
 3. The methodaccording to claim 1, wherein the series of locations are substantiallyequidistant.
 4. The method according to claim 1, wherein each of theinjectors is independently operable.
 5. The method according to claim 1,wherein the product is a liquid.
 6. The method according to claim 1,wherein the product is a gas.
 7. The method according to claim 1,wherein the priming member is a source of compressed gas which forcesthe discrete, predetermined amount of the product from the reservoirthrough the fluid conveying member to the plurality of injectors whenthe discrete, predetermined amount of the product is released inresponse to the control signal.
 8. The method according to claim 1,wherein the priming member is a pump which pressurizes the discrete,predetermined amount of the product in the reservoir to thepredetermined pressure level.
 9. The method according to claim 1,wherein the plurality of injectors are provided at a distal end of thefluid conveying member and disposed on the plurality of shanks whichrespectively place the distal end of the fluid conveying member to eachinjector at a predetermined depth in the soil.
 10. The method accordingto claim 1, wherein the product is iodomethane.
 11. A method forapplying a product to soil, comprising the steps of: providing a storagetank, which stores the product, in fluid communication with a reservoir;providing a plurality of injectors connected to the reservoir by a fluidconveying member, said plurality of injectors being disposed proximateto a plurality of shanks; priming a discrete, predetermined amount ofthe product, which is supplied from the storage tank, in the reservoirby a priming member which pressurizes the discrete, predetermined amountof the product in the reservoir to a predetermined pressure level;releasing the discrete, predetermined amount of the product, which ispressurized in the reservoir at the predetermined pressure level, inresponse to a control signal; and injecting the discrete, predeterminedamount of the product, which is released from the reservoir via thefluid communication member, under pressure at the plurality ofinjectors, wherein each injector intermittently injects the product at aseries of locations in a pass through the soil by priming the discreet,predetermined amount of the product to the predetermined pressure levelin the reservoir after each injection point, the product diffusing intothe soil from each of the injection points to provide diffusion patternsof the product in the soil wherein the method further comprisesdetermining whether an injection apparatus, which includes the storagetank, the reservoir, the fluid conveying member, the plurality ofinjectors, and the plurality of shanks, is located at one of a pluralityof injection points in the pass through the soil, wherein the reservoiris controlled by the control signal to release the discrete,predetermined amount of the product if the injection apparatus isdetermined to be located at one of the plurality of injection points inthe pass through the soil, wherein release of the discrete,predetermined amount of the product is prevented if the injectionapparatus is determined to be located between injection points, whereinthe determining whether the injection apparatus is located at one of theplurality of injection points is determined by a global positioningsatellite (GPS) sensor provided on the injection apparatus and thediscrete, predetermined amount of the product is injected if the GPSsensor indicates that the injection apparatus is located at an injectionpoint among the plurality of injection points.
 12. The method accordingto claim 11, wherein the product is a fumigant.
 13. The method accordingto claim 11, wherein the product is iodomethane.
 14. The methodaccording to claim 11, wherein the injecting comprises releasing thediscrete, predetermined amount of the product as a single charge of thereservoir, which is pressurized by the priming member, at a point in thesoil, the product volatilizing from that point to form a diffusionpattern of the product in the soil that is touching, overlapping orintermittent with diffusion patterns from adjacent points of releasingthe product as single charges of the reservoir at the injection points.15. The method according to claim 11, wherein the plurality of injectorsare provided at a distal end of the fluid conveying member and disposedon the plurality of shanks which respectively place the distal end ofthe fluid conveying member to each injector at a predetermined depth inthe soil.
 16. A method for applying a product to soil, comprising thesteps of: providing a storage tank, which stores the product, in fluidcommunication with a reservoir; providing a plurality of injectorsconnected to the reservoir by a fluid conveying member, said pluralityof injectors being disposed proximate to a plurality of shanks; priminga discrete, predetermined amount of the product, which is supplied fromthe storage tank, in the reservoir by a priming member which pressurizesthe discrete, predetermined amount of the product in the reservoir to apredetermined pressure level; releasing the discrete, predeterminedamount of the product, which is pressurized in the reservoir at thepredetermined pressure level, in response to a control signal; andinjecting the discrete, predetermined amount of the product, which isreleased from the reservoir via the fluid communication member, underpressure at the plurality of injectors, wherein each injectorintermittently injects the product at a series of locations in a passthrough the soil by priming the discreet, predetermined amount of theproduct to the predetermined pressure level in the reservoir after eachinjection point, the product diffusing into the soil from each of theinjection points to provide diffusion patterns of the product in thesoil, wherein the product is a fumigant, wherein the product is appliedto the soil in a quantity from about 3 gal/treatment acre to about 12gal/treatment acre.
 17. The method according to claim 16, wherein theproduct is iodomethane.
 18. The method according to claim 16, whereinthe priming member is a source of compressed gas which forces thediscrete, predetermined amount of the product from the reservoir throughthe fluid conveying member to the plurality of injectors when thediscrete, predetermined amount of the product is released in response tothe control signal.
 19. The method according to claim 16, wherein theplurality of injectors are provided at a distal end of the fluidconveying member and disposed on the plurality of shanks whichrespectively place the distal end of the fluid conveying member to eachinjector at a predetermined depth in the soil.